I'm using distributed application , which consists an expert and 5 slaves. Daily i receive around million queries (summation of my nodes). I want some application/Framework to arrange and log my data. I'm considering Hadoop.My strength is c,c++ and php. Can anybody please suggest me hows hadoop or maybe you will find worthwhile alternative?

And may anybody let me know what exactly are oozie ,HDFS, Pig and MapReduce? And distinction between them.

I have to know how Hadoop cluster is advantageous for small groupings?If no then what's advantageous?

Thanks ahead of time.